Bear has book on bankruptcy (5)
I believe the answer is:
bruin
'bear' is the definition.
(I've seen this before)
'book on bankruptcy' is the wordplay.
'book' becomes 'b'.
'on' means one lot of letters go next to another.
'bankruptcy' becomes 'ruin' (I've seen this before).
'b'+'ruin'='BRUIN'
'has' is the link.
(Other definitions for bruin that I've seen before include "Archetypal name for a bear" , "Conventional name for a bear" .)